1. Field of the Invention
The present invention relates to a mobile terminal, a control device and a mobile communication method. In particular, the present invention relates to a mobile communication method in which a public land mobile network (PLMN) operates in cooperation with an ad hoc network, and to a mobile terminal and a control device used in the mobile communication method.
2. Description of the Related Art
In recent years, a method of performing communication by use of direct communication between mobile terminals has been discussed in the “Mobile Ad-hoc Networks (Manet) working group” of the Internet Engineering Task Force (IETF).
As representative routing protocols in such a method, “the Ad hoc On-Demand Distance Vector (AODV) routing”, “the Dynamic Source Routing Protocol for Mobile Ad hoc Networks (DSR)” and the like are proposed.
Setting a path and transferring a packet are performed by exchanging messages by use of direct communication between mobile terminals in the Manet-related routing protocols.
In this manner, the Manet has an advantage to be capable of communication without requiring a large-scale infrastructure such as a base station or a core network in the public land mobile network.
However, the Manet requires recalculating a packet transfer route from an originating terminal to a destination terminal in cases such as when a mobile terminal to be a relay point for the packet transfer has moved. Therefore, the Manet requires exchanging messages again by use of direct communication between mobile terminals, and thus there has been a problem for the Manet to have a large amount of traffic in the direct communication between mobile terminals for the maintenance of the packet transfer route.